Cita APA (7th ed.)

ebrary, Inc, Nelson, R. J., Denlinger, D. L., & Somers, D. E. (2009). Photoperiodism: The biological calendar. Oxford University Press.

Cita Chicago (17th ed.)

ebrary, Inc, Randy Joe Nelson, David L. Denlinger, i David E. Somers. Photoperiodism: The Biological Calendar. Oxford ; New York: Oxford University Press, 2009.

Cita MLA (9th ed.)

ebrary, Inc, et al. Photoperiodism: The Biological Calendar. Oxford University Press, 2009.